A group of students completed a survey on what technology they owned. The options were: a smart watch ( S ), a tablet ( T ) or a laptop ( L ). The results of the survey are shown below. ●
● ● ● ●
36 students have a smart watch 40 students have a tablet 54 students have a laptop
14 students have a smart watch and a tablet 24 students have a tablet and laptop
If 80 people were surveyed, calculate the value of x . (b) ( S∪T )\ L (c) T′ ● ● ● 8 students have all three devices Each student owned at least one device
(i) Using the information provided, create a Venn diagram to show the results of the survey. (ii)
(iii) If a student is chosen at random, what is the probability they do not own a smart watch? (iv) Explain what the following set notations mean in words: (a) ( L∩T ) \S
Solution
x students have a smart watch and laptop, but not a tablet